A Guide to Complete Proteins
Food & Nutrition
A Guide to Complete Proteins
Chelsea S. • March 31, 2015

“Complete protein” certainly sounds like something we should be getting more of in our diets, and you’ve probably heard the term in the media before. But do you know what a complete protein is? Our simple guide will spell it out for you and let you know what your best food sources of complete protein are!

It’s important to note that there are lots of great protein sources for meat eaters and vegetarians/vegans. However, this article will exclusively focus on foods that are complete proteins on their own, not general protein sources.

What are Complete Proteins?

Proteins are an essential part of our bodies; protein is part of every cell, organ and tissue. The building blocks of protein are amino acids.

There are 20 different amino acids that combine in different ways to make all types of protein. Some amino acids can’t be produced by our bodies; therefore, we have to consume them. These are the essential amino acids.

Protein sources are grouped into one of two groups based on the amino acids they contain.

  • Complete protein sources provide all nine essential amino acids that our bodies can’t produce on their own.
  • Incomplete protein sources are low in one or more of the essential amino acids. However, incomplete proteins can be complementary, meaning that two or more incomplete protein sources can be eaten to provide an acceptable amount of all essential amino acids.

The 9 Essential Amino Acids

I was surprised that I didn't recognize many of the names of the essential amino acids. They are:










Where Can I Find Complete Proteins?

There are numerous food sources that are considered complete proteins! Your best bet for complete proteins are animal-based products; unfortunately, most plant proteins are incomplete and lack sufficient amounts of one or more essential amino acids. There are also some really great plant-based sources of essential amino acids as well.complete protein food sources

  • Animal-Sourced Complete Proteins: Meat (from cows, pigs, poultry or wild game), fish, milk and eggs all contain quality levels of the nine essential amino acids.
  • Plant-Based Sources of Complete Proteins: quinoa, buckwheat, hemp seed, chia and soy.


How Much Complete Protein Do I Need?

The Recommended Dietary Allowance (RDA) for daily protein is 46 grams for women and 56 grams for men. Protein should account for between 10-35% of daily calories. However, these numbers may vary depending on activity level and other dietary needs.

What about the essential amino acids? Well, the good news is that if you’re eating a varied diet with enough protein, you should be getting enough of the essential amino acids.

There’s no reason to worry too much about complete protein intake so long as your diet is varied. Why? Because you only need to get sufficient amounts of the essential amino acids every day, not every meal. So, a varied plant-based diet should provide your daily amino acids without much effort. Just as one example, rice and beans are two popular incomplete proteins that complement each other, providing all essential amino acids.

Want more? Greatist has a great article showing a few more examples of complementary proteins as well as some products that fit the bill (whereas this article focuses on foods that are complete protein sources on their own).

Have any questions? Let me know in the comments and I may do a follow-up article!